A variety of materials are known as so-called room temperature curing type silicone rubbers that are cured at room temperature and converted into rubbery elastic materials. These room temperature curing silicone rubbers have excellent weatherability, durability, heat resistance and freeze resistance. Because of this, these silicone rubbers are increasing used as joint sealants in the gaps between the outer walls of buildings.
However, conventional silicone sealants involve a problem in that the polyorganosiloxane, as the main component, exudes around the joints and dust in the air adheres thereto causing them to stain.
In order to solve the problem, there is proposed a method which comprises incorporating a surface active agent containing a polyoxyethylene group, a sorbitan residue or a disaccharide residue into silicone sealants (Japanese Unexamined Patent Application Laid-Open Nos. 56-76452 and 56-76453), or, alternatively, a method which comprises incorporating a surface active agent containing a fluorine atom (Japanese Unexamined Patent Application Laid-Open Nos. 58-167647 and 61-34062). However, these methods encounter a problem in that the durability of the anti-staining effect does not last very long.